Optical instrument.



G. W. SHOOK.

OPTICAL INSTRUMENT. APPLICATION FILED SEPT-5.1912.

1,236,777. Patented Aug. 14, 1917.

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GEORGE W. SHOCK, OF JACKSONVILLE, FLORIDA, ASSIGNOR TO G. W. SHOOK OPTICAL COMPANY, OF JACKSONVILLE, FLORIDA, A CORPORATION OF ARIZONA.

OPTICAL INSTRUMENT.

Specification of Letters Patent.

Patented A11 14, 1917.

Application filed September 5, 1912. Serial No. 718,737.

To all whom it may concern:

Be it known that I, Gnonen W. SHOOK, a citizen of the United States of America, residing at Jacksonville, in the county of Duval and State of Florida, have invented certain new and useful Improvements in Optical Instruments, of which the following is a specification.

The object of my invention is to provide an apparatus for oculists and Opticians which combines all the devices necessary to prove out corrections in the eye, thereby eliminating the necessity of purchasing and maintaining the large number of instruments usually found in an oculists and opticians office; and with this and minor objects in view my invention consists in the parts and combination of parts as will be hereinafter pointed out.

In the drawings:

Figure 1 is a. side elevation of the instrument embodying my invention.

Fig. 2 is a rear elevation of the cylinder mounted on the red, the rod being in section.

The reference numeral 1 designates a bracket the arm 2 of which is hollow and provided with a set screw 3 to be hereinafter referred to. 4 is a clamp secured to the other end of the bracket by means of which the instrument may be firmly secured to a table or other suitable support.

6 designates a rod constructed to telescope in the hollow arm 2 of the bracket 1. The. set screw 3 is constructed to clamp this rod in any adjusted position relative to the arm 2. The upper end of the rod 6 is yoked as at 7 in which is pivoted a plate 8 adapted to be clamped in any desired position in the yoke by means of the set screw 9.

10 is a rod rigidly secured to the plate 8 on one end of which the hood or head piece 11 is secured.

A clamp 39 is slidably mounted on the rod 10 on whlch is secured a plate 41. 40 are friction springs constructed to hold the sliding bracket in any adjusted position on the rod 10.

A plate or shelf 41 is fixed to the sliding bracket on which is hinged at 41 a cylinder 42 in which is journaled a drum 43. I arrange a series of letters of varying sizes on the periphery of the drum which may be viewed by the patient through the slot 44 in the cylinder.

is a black target having a small circular central space 46 said target being pivoted at 47 to the shelf 41. When the target is in use the cylinder is swung to one side on its hinge 41 In treating a patient the hood is placed against the face, the hood to fit snugly against the forehead with the guards 26 and 27 fitting closely against the sides of the head whereby all rays of light are excluded from the eyes except those passing through the usual openings in the hood. The drum is then placed at twelve inches from the hood, which is the normal reading distance, and is then revolved and the patient indicates the size of type which he can easily read at that distance without the aid of lenses. The drum is then advanced toward the hood to determine the near point of vision and the strength of the convex lens needed for correcting the hypermetropia. I then place the trial lens 31 in the lens holder 29.

By this test the operator is enabled to make a certain summary of the defects existing in the eye of the patient. The cylinder is then swung to one side on its hinge and the patient directed to look at the target 45, one eye being closed by means of a blank placed in the lense carrier, and his statement as to the appearance of the small white circular space will indicate to the operator the distance limit. The target is used to define the astigmatic condition of the eye and also to afford proof of the correction. Various sized targets are provided with each instrument to determine various distance corrections, the smaller target proving the correct reading distance.

After the range of vision has been determined lenses are placed in the lens holder 29 which demonstrate the corrections in each eye whereupon both eyes are tested simultaneously. In the simultaneous test of both eyes I have frequently found that it is necessary to neutralize, to some extent, the lenses for the two eyes and I am enabled to do this by reason of the pair of openings in the hood. In actual practice it has been found, as above stated, that while an accurate fit may be made in the lenses for each eye sepa rately, yet the patient is unable to see clearly when the lenses are mounted in the usual frame, whereas by giving the binocular treatment, I am enabled to rectify this and neutralize the two lenses simultaneously, thus relieving the patient of inconvenience, giving him the benefit of an accurate correc tion.

In using the hood as a carrier for the trial lenses I eliminate the necessity for using the usual trial frames which are objectionable by reason of its combined weight and the weight of the lenses resting directly on the nose which, in the event of the patientbeing nervous, results in creating an abnor mal condition in the eye which frequently results in an improper correction.

lVhat I claim is 1. In an optical instrument, the combination with a support, of a bar, a shelf slidably mounted on said bar, and test card cyl indcr hinged at one end to said shelf, whereby it may be swung to one side of the bar to permit an unobstructed vision, a drum revolubly mounted in said cylinder and provided with a thumb piece for revolving it.

2. In an optical instrument, the combination with a support, of a bar having vertically adjustable pivotal connection with said support, a shelf slidably mounted on said bar, a cylinder having an opening and hinged at one end to said shelf whereby it may be swung to one side of and below the bar to afford an unobstructed vision, a test card drum revolubly mounted in said cylinder and provided with a thumb piece for revolving it, and a target pivotally mounted on said shelf back of the cylinder and constructed to be swung from side to side.

In testimony whereof I affix my signature in presence of two witnesses.

GEORGE WV. SHOOK.

\Vitnesses EDWIN S. CLARKSON, J. M. YVYNKooP.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, .D. C 

